In a moving situation, something to hang on to (5)

I believe the answer is:

strap

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'something to hang on to' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for strap that I've seen before include "Shoulder band" , "Parts of leather belt" , "Fastening strip" , "Leather thong" , "Restraining fastener" .)

I've seen this clue in the Evening Standard.

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